Finding the Third Proportional to 30,128.50 and 65,619

Step by Step Solution

1. Step 1: Write the proportion equation
   30,128.50 : 65,619 = 65,619 : x
2. Step 2: Convert to fraction form
   30,128.50/65,619 = 65,619/x
3. Step 3: Cross multiply
   30,128.50x = 65,619 × 65,619
4. Step 4: Simplify right side
   30,128.50x = 4,305,853,161
5. Step 5: Solve for x
   x = 4,305,853,161/30,128.50
6. Step 6: Final answer
   x = 142,916.28